The present invention relates to an agricultural chemicals formulation for a rice paddy field, to scatter (apply) directly on the water surface, and more in detail, it relates to an agricultural chemicals formulation for a rice paddy field suitable for the agricultural chemicals being scattered (applied) uniformly by throwing a granular agricultural chemicals composition packed in a bag made of a water-soluble film and the like directly on the water surface of a rice paddy field filled with water, the preparation thereof and the method for scattering (applying) the same.
At present, as a major agricultural chemicals formulation, a granulated type, a powder type, emulsifiable type, wettable type, suspension type, granulated hydrate type and so on are known. However, in recent years, saving labor for scattering (applying) agricultural chemicals and cutting down of agricultural chemicals have become important and improvement of the formulation form of the agricultural chemicals is required.
Under these circumstances, recently, labor-saving formulations which can be scattered (applied) only by throwing the agricultural chemicals from a path between rice paddy fields without entering into the rice paddy has been studied. Such a formulation is premised on being scattered in a rice paddy field unevenly, and therefore it has been demanded to develop a formulation whose agrochemically active ingredients float and spread on the water surface to obtain a desirable spreadability of the components.
Various studies have been made for such a demand, but actually no agricultural chemicals formulation has been obtained, which are perfectly satisfactory for agrochemically active ingredients having various properties. For instance, a method to pack emulsion containing an agrochemical insecticide ingredient of a water-soluble film and to throw it into a paddy field filled with water is disclosed (Japanese Patent Publication No. Sho 42-5240). However, the technology disclosed here has a disadvantage that a large quantity of the agricultural chemicals ingredients remain in the soil at the point of throwing after the treatment.
Various technologies have been disclosed, for instance, a formulation in which agrochemically active ingredients are impregnated into a foamed plastic material having particle sizes of 0.1 mm to 10 mm and packed with a water-soluble film (Japanese Patent Laid-open No. Sho 53-99327); an agricultural chemicals formulation for throwing into a paddy field in which water-floatable solid agricultural chemicals containing an agrochemically active ingredient, a water-floatable granular nucleus chosen from calcined vermiculite, foamed pearlite, foamed shirasu, and cork, a surfactant (acetylene alcohol) are packed with a water-soluble film (Japanese Patent Laid-open No. Hei 6-336403); and a formulation in which agrochemically active ingredients of agricultural chemicals are coated on and carried by a granular nucleus such as pumice or calcined pearlite having apparent specific gravity of less than 1 and particle sizes of 0.3 mm to 1.4 mm and packed with a water-soluble film (Japanese Patent Laid-open No. Hei 9-183701). However, there may arise a problem in spreadability of the components because a portion of the formulation precipitates on the bottom at the point of the treatment, and a disadvantage that since much quantity of the agrochemically active ingredient still remain on the granular nucleus made of a foamed plastic material, pumice, calcined pearlite, or the like after the treatment, the desired effect of the agricultural chemicals can not be exhibited but, on the contrary, phytotoxicity may arise from bringing the agricultural chemicals gathered together by the wind.
Furthermore, a granular water-floatable insecticide in which an insecticide is coated on actatic polypropylene granules using a binder (Japanese Patent Publication No. Sho 45-9560), a floatable granular formulation in which an insecticide component is firmly fixed on calcined pearlite with polybutene (Japanese Patent Publication No. Sho 47-1240) are known, however, since much quantity of the agrochemically active ingredients remain on the granular nucleus, as similarly as above, the result is not only that the desired effect of the agricultural chemicals can not be exhibited but phytotoxicity may arise because the agricultural chemicals are gathered together by the wind.
In addition, in the conventional art, it has been difficult to obtain a scattering type formulation enabling labor-saving application containing agrochemically active ingredients which are liquid at room temperature.
In an agricultural chemicals formulation to be thrown directly into a rice paddy field filled with water to be scattered, an object of the present invention is to provide a composition having an excellent spreadability without stagnation of agrochemically active ingredients at the point of treatment, and in particular, to realize a labor-saving scattering (application) type formulation in a liquid state at room temperature containing agrochemically active ingredients, which has been hitherto difficult to realize, and further to make the formulation contain a high concentration of the agrochemically active ingredients in a liquid state at room temperature.
As a result of assiduous study to obtain a labor-saving scattering (application) type formulation containing an agrochemically active ingredient, especially that in a liquid state at room temperature, as an effective component, the present inventors have found that when the agrochemically active ingredient is made into a liquid matter together with a surfactant and a substance having a thickening function or a gelation function in the water, which is then packed with a water-soluble film after it is carried by a granular nucleus, it becomes possible to be scattered (applied) on a rice paddy field only by being thrown from a path between the paddy fields without entering into the paddy fields and, in addition, it has excellent spreadability, and based upon this finding, the inventors have accomplished the present invention.
The present invention is to provide an agricultural chemicals formulation for a rice paddy field, which is characterized by that a granular composition in which an active ingredient of the agricultural chemicals in a liquid state at room temperature, a surfactant, and a substance exhibiting a thickening function or a gelation function in the water are carried by granular nucleuses is packed with a water-soluble film.
In addition, the present invention is to provide a method of producing an agricultural chemicals formulation for a rice paddy field, comprising the steps of preparing a granular composition by letting a granular nucleus hold and carry a liquid agrochemically active ingredient at room temperature, a surfactant, and a substance exhibiting a thickening function or a gelation function in the water and packing thus obtained granular composition in a water-soluble film.
Furthermore, the present invention is to provide a method of scattering (applying) an agrochemically active ingredient, comprising the steps of throwing directly the agricultural chemicals formulation for a rice paddy field in a paddy field filled with water at a rate of 2 to 20 bags per 10 a.